TomB Posted March 26, 2012 Share Posted March 26, 2012 Ive just got the 7 back on the road after removing the tank to replace gaskets. First full fill up on Sunday, check the pump gaskets is fuel tight after about 20 minutes of driving and there is fuel everywhere. As Im now in the middle of nowhere (well Rochdale ) I press on with my blat and recheck it after Ive used some fuel. Now everything is bone dry and it stays that way until I got home with half a tank on board. Tonight I go back to fill up to try and see whats happening and there is fuel dripping from the pump and running along the bottom of the tank. Upon further investigation, it appears the weld around the breather pipe adjacent to the filler has a crack around it, and draining and refilling 5 litres of fuel showed it bubbling around here. I must have positioned the fairly rigid rubber pipe or the boot floor in such a way,to put downward force on the breather pipe which has cracked the weld. As it only appears to be a problem at filling or very full, Im going to try a temporary repair with some sort of epoxy or chemical metal around the weld. Any experience/ comments in this respect, or a recommended and readily available product? Link to comment Share on other sites More sharing options...
Doug Posted March 27, 2012 Share Posted March 27, 2012 How odd, I have had exactly the same thing this weekend too. Rather than buy a new tank or removing the existing one and risking having it welded, I've used one of the epoxy metal products to fill and bond the crack around the breather. The stuff I used comes in a swiss roll type pack with all the constituent parts in the roll. All you do is cut a bit off and manipulate it in your hand until it's mixed. Carefully apply and, hopefully Bob's your uncle. Hopefully the terrible fuel smell having filled up will be a thing of the past now! Link to comment Share on other sites More sharing options...
glasgow Posted March 27, 2012 Share Posted March 27, 2012 I recently used a tube of tank seal from halfords... only costs around 5 pounds.. just tried to get you its name but halfords website is down now... will try again later... Ahmed Link to comment Share on other sites More sharing options...
tiddy1 Posted March 27, 2012 Share Posted March 27, 2012 The epoxys are pretty good, you can even use areldite, which has worked remarkably well on my tank for the last 5 years Link to comment Share on other sites More sharing options...
Support Team Shaun_E Posted March 27, 2012 Support Team Share Posted March 27, 2012 My tank cracked in the same place - tank seal worked for me as well. Link to comment Share on other sites More sharing options...
TomB Posted March 27, 2012 Author Share Posted March 27, 2012 Thats interesting - all you have said repair with epoxy type stuff, and the two folk Ive been in contact with on my phone, said remove & weld! Given Ive spent the last four months stripping the rear end, cleaning and rebuilding, I really dont want to remove the tank again. Would using a repair product make a proper welded repair, say next winter, more difficult, or can the putty be removed with a sharp knife or Dremel grinder? Link to comment Share on other sites More sharing options...
glasgow Posted March 27, 2012 Share Posted March 27, 2012 you dont need to remove it... it will be solid for years.. Edited by - Glasgow on 27 Mar 2012 09:35:16 Link to comment Share on other sites More sharing options...
Area Representative z7 Posted March 27, 2012 Area Representative Share Posted March 27, 2012 I had a similar problem recently. here's my thread. I used JB Weld for the repair and all seems OK so far. z7 Link to comment Share on other sites More sharing options...
Doug Posted March 27, 2012 Share Posted March 27, 2012 The stuff I used is this stuff. The repair looks very good this morning, having done it yesterday. Make sure the area is thoroughly clean and it should last for years. Link to comment Share on other sites More sharing options...
TomB Posted March 27, 2012 Author Share Posted March 27, 2012 Well as I need to get it fixed for an early Sunday blat, and possibly an area meet tomorrow, Im going to try and find this Araldite product in Halfords tonight. Araldite is a trusted brand, and it sounds on paper very similar to the Quick Steel and JB Weld products. Link to comment Share on other sites More sharing options...
glasgow Posted March 27, 2012 Share Posted March 27, 2012 apply two layers and make sure you dont do it in the garage at night (temp should be above 15 celius Link to comment Share on other sites More sharing options...
Area Representative Paul Richards Posted March 27, 2012 Area Representative Share Posted March 27, 2012 Tom Steel Weld will do a brilliant job - I've used on race tanks before and we mended Sarah's exhaust manifold with it on the Picos trip. I could hardly believe it withstood those temperatures. I have a new one if you want it. You can buy a replacement from Car and Garage in Haslingden. If you use it, make sure you roughen up the surface to provide a key. Apply Weld Steel and hold temporarily in place with gaffer tape until set fully. Removing and re-welding will of course be a better more permanent repair. Link to comment Share on other sites More sharing options...
TomB Posted March 27, 2012 Author Share Posted March 27, 2012 Thanks Paul, Ill be in touch if Halfords dont have any of the Araldite product in stock tonight. Knowing what Aralidite epoxy adhesive is like normally, I can only imagine what it would be like with steel grains in it. Dont want to get that on my best jumper Link to comment Share on other sites More sharing options...
MartinWoodham Posted March 27, 2012 Share Posted March 27, 2012 being a cynic, I suspect that those advising removal and welding are people who do removal and welding......... I must check the source of my petrolly smell, just as soon as I can work out how to get the boot floor loose after CC Midlands bonded it in with fireproof mastic. Anyone got any det cord? Link to comment Share on other sites More sharing options...
TomB Posted March 27, 2012 Author Share Posted March 27, 2012 Well, I bought this Evo-Stik product from Halfords. I thought a putty would be good as I can build it up around the weld and breather pipe. My only niggly doubt is that is doesn't implicitly say its fuel resistant and I cant find a data sheet online. Are most epoxy products fuel resistant? Link to comment Share on other sites More sharing options...
glasgow Posted March 28, 2012 Share Posted March 28, 2012 Tom, not sure have you fixed yous tank or not yet, but this is the stuff I got from halfords (specific for petrol tanks) here Link to comment Share on other sites More sharing options...
TomB Posted May 11, 2012 Author Share Posted May 11, 2012 Ballcocks!!! Double ballcocks to be precise. Ive had suspicions that fuel has seeped under the chemical metal plug when filling up after a couple of spots of fuel under the car. Ive let the car run super low on fuel and went to fill up tonight. I trickled fuel in while watching the top of the tank by the filler neck and saw some fuel trickling out. First ballcock. After Id put in 5 litres I checked under the car, and fuel was more or less, pouring from the bottom of the fuel pump gasket. Double ballcocks. So I really do need to remove the fuel tank now, cut off the chemical metal, clean the inside of the tank out as best I can for welding, remove the pump and work out why the gasket (James Whiting type) is leaking. Would running the fuel too low effect the integrity of the gasket? When I refitted the pump & gasket I used a smear of blue hylomar on each side of the gasket. Why/ how is the breather neck weld cracking? I think the corresponding pipe on the metal filler neck assembly is too long and not perfectly lined up with the neck on the tank, and the short distance between the two with the old stiff rubber hose connecting it has strained the weld leading to cracking. Link to comment Share on other sites More sharing options...
Paul Deslandes Posted May 12, 2012 Share Posted May 12, 2012 the pump and fuel gauge gaskets can leak if the screws have been over tightened. The tank flange distorts enough to create a small gap that the gasket doesn't fill. While you've got your tank out, which I'm guessing is going to have to happen to sort your other leak, very carefully check the flatness of the mating flanges with a straight edge and gently reshape. Also check that the rivnuts and hankbushes are tight and flush. A small amount of suitable sealant might help but its better to get the mating faces right first. Link to comment Share on other sites More sharing options...
TomB Posted May 15, 2012 Author Share Posted May 15, 2012 I took the boot floor and filler pipework out last night. The breather pipe on the tank doesn't line up with the corresponding connector on the metal filler neck assessbly, so I think that the stiff and old short rubber hose has stressed and cracked the weld. Ill post a photo later to show the misalignment. So now Im wondering why - should I have some form of rubber gasket between the filler neck and the car skin, such as this? which might help with alignment? What is this grommet for? I havn't yet fiddled with the tank position to see if I can get the tank inlets to line up better with the filler neck - but it strikes me that the tank positioning and fastening is quite vague. It sit on the cradle and is then tightened with the straps, but this serves to pivot the tank back and up and never really holds it securely. If the tank is secured so that it remains flat against the cradle, it doent feel particularly secure. Should there be a gap between the rear skin and the tank of about 0.5inch? I have the race ali armour on the back of the car, and with the boot floor removed I can see through to the floor. Does that sound right/ normal? Another query is on the fuel pump gasket/ pump face - the Caterham supplied gasket here has three locating nipples which correspond to the pump face - these are absent on the James Whiting gasket. Are these nipples just for gasket location or are they needed to keep it all fuel tight? Edited by - TomB on 15 May 2012 09:04:46 Link to comment Share on other sites More sharing options...
Paul Deslandes Posted May 15, 2012 Share Posted May 15, 2012 not certain but I think that grommet is for the really old style flip-top filler cap. The filler fits through the grommet and then an 'elephants trunk' hose connects to the tank neck. I can't find it on the Caterham parts site but its the nice old fashioned chromed filler. Link to comment Share on other sites More sharing options...
TomB Posted May 15, 2012 Author Share Posted May 15, 2012 Thanks Paul for your help. By inference, the only take up for any movement of the tank in my flat Metro capped car, is the connecting hoses between the metal filler neck and the tank, seeing as the filler is directly attached to the rear skin, Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted May 15, 2012 Leadership Team Share Posted May 15, 2012 That's correct. Metal filler is bolted directly to the skin (IIRC 2 self-tapping screws) and the filler is then connected to the pipe on the tank via the large hose. Only option is to fit the tank loosely, connect the filler, then secure the tank without placing undue strain on the hose. Suggest though that you first get the tank repaired properly 😬 Stu. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now